High pressure extraction of oil seed

For calculation of phase equilibria of the system seed oil/CO₂, an equation of state published in the literature has been fitted to experimental data of that system. The results thus obtained are of only limited use in designing a supercritical extraction process. The experimental investigation of the mass transfer kinetics is much more significant. Mechanical processing of the oil seed’s cell wall structure has been shown to be of great importance. The best specific yields were achieved with material that had been mechanically pre-deoiled and thereby broken open. Yields are increased considerably by use of the gas mixture CO₂/propane or other special gas mixtures or by the addition of refrigerants. However, the extraction times achieved in batch operation, together with the mass product nature of oil seed, make a continuous supercritical extraction essential if operation is to become economic relative to the conventional hexane extraction. To this end, the energetics of the process have been calculated, and practical possibilities for continuous operation are discussed. Presented at the International Symposium, “High Pressure Chemical Engineering,” Erlangen, in October 1984.     

Evidence that atypical protein kinase C-lambda and atypical protein kinase C-zeta participate in Ras-mediated reorganization of the F-actin cytoskeleton

Liver fatty acid binding protein (L-FABP) appears to contain several different forms that may result from post-translational modification or bound ligand. To further assess this possibility, L-FABP was purified from rat liver homogenate and two putative isoforms separated using a sulfonyl column, a strong cation exchange resin. Fraction I eluted at 0.2 M NaCl, had a pI of 7.59, and following a final size exclusion step contained > 98% L-FABP. Fraction II eluted at 1.0 M NaCl, had a pI of 7.59, and following a final size exclusion step contained > 99% L-FABP. Both fractions contained approx. 0.15 moles of endogenous bound fatty acid per mole of protein, while L-FABP not subjected to the cation exchange step contained 0.75 moles of fatty acid per mole of protein. Fractions I and II had a greater proportion of saturated and monounsaturated fatty acids with a large reduction in polyunsaturated fatty acids compared to L-FABP not fractionated by cation exchange. Mass spectral analysis indicated the molecular mass of Fraction I was 14,315.02 +/- 0.35 Da and Fraction II was 14,315.86 +/- 0.34 Da. The peptide map for each fraction was determined by limited digestion of each fraction with either trypsin, Asp-N, or chymotrypsin to yield overlapping peptide fragments. Mass spectral analysis of these digests indicated the two proteins had identical amino acid fragments and that Cys69 was reduced and there were no Asn to Asp exchanges. Hence, these two forms of L-FABP were not isoforms and were not the result of differences in bound fatty acid. It is proposed that these two distinct forms of rat L-FABP were structural conformers based on two alternative folding pathways.     

Reactions of non pregnant and and of cattle at different stages of pregnancy from the Holstein Friesian breed (HF) and from the old type German black and white breed (DSB) exposed to transport stress: variation and individual reaction patterns of hormone metabolic and hematologic variables

Breeding animal transports between parts of our institute were used assessing effects of age of animals, of breed, of their functional state and of individual specificity of reaction patterns using peripheral venous blood samples. Increased mean values of Hb, Hk, body temperature, total protein, albumin, FT4, T4, FT3, T3, cortisol, adrenaline and decreased ones of body weight, Pa, Fe, noradrenaline were found after transport stress. Comparing age matched groups of DSB and HF breed higher concentrations of total protein, creatinine, lactate, cortisol, FT4, T3 and FT3 and lower ones of albumin, blood urea and Fe could be observed in animals of DSB breed before and after transport. Strong correlations existed on 14 variables within animals before and after transport stress meaning there could be individual specificity of some blood parameters.